Build vs Buy: The Silicon Decision

In this episode of Run the Numbers, CJ Gustafson talks with Rivian CFO Claire McDonough about financing one of the most capital-intensive businesses in the world. They cover long-term investment decisions, capacity planning, cash management as production scales, lessons from Rivian’s nearly $14B IPO, the risks of over- and under-building, and why federal EV tax credits matter more than most people think.

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SPONSORS:

Tabs is an AI-native revenue platform that unifies billing, collections, and revenue recognition for companies running usage-based or complex contracts. By bringing together ERP, CRM, and real product usage data into a single system of record, Tabs eliminates manual reconciliations and speeds up close and cash collection. Companies like Cortex, Statsig, and Cursor trust Tabs to scale revenue efficiently. Learn more at https://www.tabs.com/run

Abacum is a modern FP&A platform built by former CFOs to replace slow, consultant-heavy planning tools. With self-service integrations and AI-powered workflows for forecasting, variance analysis, and scenario modeling, Abacum helps finance teams scale without becoming software admins. Trusted by teams at Strava, Replit, and JG Wentworth—learn more at https://www.abacum.ai

Brex is an intelligent finance platform that combines corporate cards, built-in expense management, and AI agents to eliminate manual finance work. By automating expense reviews and reconciliations, Brex gives CFOs more time for the high-impact work that drives growth. Join 35,000+ companies like Anthropic, Coinbase, and DoorDash at https://www.brex.com/metrics

Metronome is real-time billing built for modern software companies. Metronome turns raw usage events into accurate invoices, gives customers bills they actually understand, and keeps finance, product, and engineering perfectly in sync. That’s why category-defining companies like OpenAI and Anthropic trust Metronome to power usage-based pricing and enterprise contracts at scale. Focus on your product — not your billing. Learn more and get started at https://www.metronome.com

RightRev is an automated revenue recognition platform built for modern pricing models like usage-based pricing, bundles, and mid-cycle upgrades. RightRev lets companies scale monetization without slowing down close or compliance. For RevRec that keeps growth moving, visit https://www.rightrev.com

Rillet is an AI-native ERP built for modern finance teams that want to close faster without fighting legacy systems. Designed to support complex revenue recognition, multi-entity operations, and real-time reporting, Rillet helps teams achieve a true zero-day close—with some customers closing in hours, not days. If you’re scaling on an ERP that wasn’t built in the 90s, book a demo at https://www.rillet.com/cj

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LINKS: 

Claire on LinkedIn: https://www.linkedin.com/in/claire-rauh-mcdonough-5291b946/

Rivian: https://rivian.com/

CJ on LinkedIn: https://www.linkedin.com/in/cj-gustafson-13140948/

Mostly metrics: https://www.mostlymetrics.com

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RELATED EPISODES:

Why Revenue Recognition Is the Next AI Battleground | Dan Miller of RightRev

https://youtu.be/TxhTtwmOass

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TIMESTAMPS:

00:00:00 Craziest Expense Story at Rivian

00:01:22 Intro to Claire McDonough

00:03:09 Capital Intensity and Vertical Integration at Rivian

00:06:44 Raising $14B: How Rivian Planned Its IPO Capital

00:10:22 Capacity Planning and Scaling R2 Production

00:12:13 Sponsors — Tabs, Abacum, Brex

00:15:34 Sweating Existing Capacity vs Overbuilding

00:18:22 Winning EV Adoption from ICE Buyers

00:22:27 How Federal EV Tax Credits Shape EV Pricing

00:26:03 Sponsors — Metronome, RightRev, Rillet

00:29:27 R2 as a Driver of Long-Term Profitability

00:33:14 Supply Chain as the Critical Path to Launch

00:36:53 Product Roadmap as the Anchor for Capital and Headcount

00:39:40 Peloton and Flipkart Lessons from Banking

00:43:42 Biggest Career Mistake

00:44:50 Advice to Younger Self

00:47:19 Rivian’s Finance Software Stack